1. Field of the Invention
The present invention relates, in general, to heat exchangers used in refrigeration systems and, more particularly, to a water-cooled heat exchanger used to condense a refrigerant in such a refrigeration system.
2. Description of the Related Art
As is well known to those skilled in the art, a refrigeration system used with air-conditioning apparatuses includes a compressor, a refrigerant-condensing heat exchanger, a refrigerant-expansion unit, and a refrigerant-evaporating heat exchanger, which are sequentially connected to each other by a refrigerant pipe to create a refrigeration circuit. When the compressor of the refrigeration circuit is operated, a refrigerant circulates through the refrigerant pipe while repeatedly changing its phase by transferring heat to or absorbing heat from the surroundings. The refrigerant system thus cools room air.
In such a refrigeration system used with air-conditioning apparatuses, the refrigerant-condensing heat exchanger comprises a refrigerant-distributing header which distributes an outlet refrigerant of the compressor to a plurality of heat exchanging tubes, and a refrigerant-gathering header which gathers the condensed refrigerant flowing from the heat exchanging tubes, prior to feeding the gathered refrigerant to the refrigerant-expansion unit. A plurality of heat exchanging fins having a thin plate shape are assembled with the heat exchanging tubes so as to enlarge the heat exchanging area, at which outdoor air comes into contact with the heat exchanger. During an operation of such a refrigerant-condensing heat exchanger, outdoor air, which is forced by a blower fan installed adjacent to the heat exchanger, cools the tubes and fins, thus condensing the refrigerant flowing in the tubes. The phase of the refrigerant in the refrigerant-condensing heat exchanger is thus changed from a gas phase into a liquid phase.
However, such a conventional refrigerant-condensing heat exchanger used with refrigeration systems is problematic in that the heat exchanger is cooled only by the air forced by the fan, so the improvement of heat exchanging efficiency is undesirably limited. In addition, the above heat exchanger must have a plurality of heat exchanging fins to enhance the heat exchanging efficiency, so the size of the heat exchanger is undesirably enlarged to accomplish the desired heat exchanging effect. The enlarged size of the heat exchanger undesirably increases the size of a refrigeration system which uses the heat exchanger.